concepts.dsl.expression#

Data structures for expressions in a DSL.

All classes extend the basic Expression class. They can be categorized into the following groups:

ObjectOrValueOutputExpression is the base class for expressions that output objects or values. This is only used for type hinting.
ObjectOutputExpression and ValueOutputExpression are the expressions that output objects or values.
VariableExpression which is the expression that refers to a variable.
VariableAssignmentExpression which assigns a value to a variable.

Under the ValueOutputExpression category, there are a few sub-categories:

NullExpression which is the expression that outputs a null value.
ConstantExpression which is the expression that outputs a constant value.
ListCreationExpression which is the expression that creates a list.
ListExpansionExpression which is the expression that expands a list into a sequence of values (e.g., plan steps).
FunctionApplicationExpression which represents the application of a function.
ListFunctionApplicationExpression which represents the application of a function to a list of arguments.
BoolExpression which represents Boolean operations (and, or, not).
QuantificationExpression which represents quantification (forall, exists).
GeneralizedQuantificationExpression which represents generalized quantification (iota, all, counting quantifiers).
FindOneExpression which represents the find-one quantification.
FindAllExpression which represents the find-all quantification.
PredicateEqualExpression which represents the equality test between a state variable and a value.
ObjectCompareExpression which represents the comparison between two objects.
ValueCompareExpression which represents the comparison between two values.
ConditionExpression which represents the ternary conditional expression.
ConditionalSelectExpression which represents the conditional selection for some computed value.
DeicticSelectExpression which represents the deictic selection for some computed value (i.e., forall quantifiers).
BatchedExpression which is the expression that assigns values to state variables with batched expressions.

Under the ObjectOutputExpression category, there are a few sub-categories:

ObjectConstantExpression which is the expression that outputs a constant object.

Under the VariableAssignmentExpression category, there are a few sub-categories:

AssignExpression which is the expression that assigns a value to a state variable.
ConditionalAssignExpression which is the expression that assigns a value to a state variable conditionally.
DeicticAssignExpression which is the expression that assigns values to state variables with deictic expressions (i.e., forall quantifiers).

The most important classes are: VariableExpression, ObjectConstantExpression, ConstantExpression, and FunctionApplicationExpression.

Functions

`cvt_expression`(expr[, dtype])	Convert an expression compatible object to an expression.
`cvt_expression_list`(arguments[, dtypes])	Convert a list of expression compatible objects to a list of expressions.
`get_type`(value)	Get the type of the given value.
`get_types`([args, kwargs])	Get the types of the given arguments and keyword arguments.
`is_and_expr`(expr)
`is_constant_bool_expr`(expr)
`is_exists_expr`(expr)
`is_forall_expr`(expr)
`is_implies_expr`(expr)
`is_not_expr`(expr)
`is_null_expression`(expr)
`is_object_output_expression`(expr)
`is_or_expr`(expr)
`is_value_output_expression`(expr)
`is_variable_assignment_expression`(expr)
`is_xor_expr`(expr)

Classes

`AndExpression`
`AssignExpression`
`BatchedExpression`
`BoolExpression`
`BoolOpType`
`CompareOpType`
`ConditionExpression`
`ConditionalAssignExpression`
`ConditionalSelectExpression`	Conditional select expression represents the selection of a value based on a condition.
`ConstantExpression`	Constant expression always returns a constant value.
`DeicticAssignExpression`
`DeicticSelectExpression`
`ExistsExpression`
`Expression`	Expression is an abstract class for all expressions in the DSL.
`ExpressionDefinitionContext`
`FindAllExpression`
`FindOneExpression`
`ForallExpression`
`FunctionApplicationExpression`	Function application expression represents the application of a function over a list of arguments.
`GeneralizedQuantificationExpression`
`ImpliesExpression`
`ListCreationExpression`
`ListExpansionExpression`
`ListFunctionApplicationExpression`	Function application expression represents the application of a function over a list of arguments.
`NotExpression`
`NullExpression`
`ObjectCompareExpression`
`ObjectConstantExpression`
`ObjectOrValueOutputExpression`
`ObjectOutputExpression`
`OrExpression`
`PredicateEqualExpression`	This function is obsolete and should be replaced by `ValueCompareExpression`.
`QuantificationExpression`
`QuantificationOpType`
`ValueCompareExpression`
`ValueOutputExpression`
`VariableAssignmentExpression`
`VariableExpression`
`XorExpression`

Exceptions

`DSLExpressionError`
`FunctionApplicationError`